Vibrations! (Ads)

Vibrations is an app for measuring mechanical vibrations and acoustic noise from engines, the environment, machines, and other equipment. (Ads supported.)

This is (currently) the only app that combines acoustic *and* mechanical measurements!

Uses: monitoring vehicle engine vibration, monitoring vibrations of household appliances (dishwasher, refrigerator, waste disposal units, clothes dryers, etc.), measuring g-force in moving vehicles, helping to identify failing gears, evidenced by knocking sounds, modes, etc..

Vibrations uses data streams from the built-in accelerometer and microphone: it calculates two simultaneous FFTs, one from the mechanical measurements, one from the audible measurements. It then shows the frequency spectra on the screen. The frequency axis is labelled in Hz and RPM (revolutions per minute).

Four on-screen software gauges give an overview of the measurements:

1) The g-force (excluding gravity), which measures acceleration

2) The frequency of the current peak in the mechanical/vibration noise

3) The frequency of the current peak in the acoustic noise

4) The sample rate at which mechanical vibrations are being measured

Screen shots can be taken using the "Save Screen" button, and stored to the SD card.

Time series of accelerometer data (up to 20 seconds) can be recorded and saved using the "Record Data" button. Since data are continually being gathered, the recorded data written to the file actually starts a second or so *before* the button was pressed. Recording can be interrupted while in progress, and the data discarded or saved. Otherwise, the recording will automatically terminate after 20 seconds have elapsed, and the data discarded or saved then.

Data collection for the screen and record mode can be paused and resumed using the "Pause"/"Resume" button.

Please contact me if you have suggestions for improvements or enhancements (or to report problems).

Also, please note that the frequency limit of the mechanical vibration measurement is limited by the maximum rate that accelerometer samples can be obtained from the Android device: this typically varies from device to device - e.g. on the Nexus 7 and 10 tablets, the rate is ~200 samples/sec, giving a maximum frequency measurement of ~100Hz or 6000 RPM. On the Galaxy S3 the rate is ~100 samples/sec, giving a maximum frequency of ~50Hz.振动是一个应用程序，用于测量从发动机，环境，机械，及其他设备的机械振动和噪声。 （广告支持）。

这是目前唯一的应用程序，结合了声*和*机械测量！

用途：用于监控车辆发动机振动监测振动家电（洗碗机，冰箱，垃圾处理单位，干衣机等），测量G-力在移动的交通工具，帮助确定失败齿轮，证明了敲门的声音，方式等..

振动从内置的加速度计和麦克风使用数据流：同时计算两个的FFT，一个从机械测量，从发声测量之一。然后，它显示在屏幕上的频谱。频率轴上的标记为（赫），RPM（每分钟转数）。

四个屏幕上的软件压力表测量给出一个概述：

1）G力（不包括重力），测量加速度

2）在机械/振动噪声的电流峰值的频率

3）在声学噪声的电流峰值的频率

4）机械振动被测量的采样率

屏幕截图可以使用“保存屏幕”按钮，并存储到SD卡上。

加速度计数据的时间序列（最多20秒），可以记录和保存使用“记录数据”按钮。由于数据不断地收集，记录的数据写入到文件中，居然开始*前*按钮被按下，一秒钟左右。录音可以被打断，而在进步，丢弃或保存数据。否则，记录将自动终止后经过20秒，然后丢弃或保存数据。

数据采集​​的屏幕和记录模式，可以使用“暂停”/“恢复”按钮暂停和恢复。

请与我联系，如果您有任何建议改进或增强（或报告问题）。

另外，请注意，加速度样品可以从Android设备获得的最大速率是有限的机械振动测量的频率限制：这通常不同从设备到设备 - 例如的Nexus 7和10片，税率为〜200样本/秒，给人〜100Hz或6000转的最大频率测量。在Galaxy S3率100样本/秒，给人的最大频率为50HZ〜。